body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: #f8f9fb;
  display: flex;
  min-height: 100vh;
}
header {
  position: fixed;
  top: 0;
  left: 200px;
  right: 0;
  height: 60px;
  background: #2d3e50;
  color: white;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 20px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.1);
  z-index: 10;
}
.logo { font-weight: bold; }
.sidebar {
  width: 200px;
  background: #34495e;
  color: white;
  position: fixed;
  top: 0;
  bottom: 0;
  padding-top: 70px;
}
.sidebar ul { list-style: none; padding: 0; margin: 0; }
.sidebar li a {
  display: block;
  padding: 10px 20px;
  color: white;
  text-decoration: none;
  border-bottom: 1px solid rgba(255,255,255,0.05);
}
.sidebar li a:hover { background: #2c3e50; color: white; }
.content { margin-left: 220px; padding: 80px 20px; flex-grow: 1; }
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 20px; }
.card { background: white; padding: 20px; text-align: center; border-radius: 10px; box-shadow: 0 1px 4px rgba(0,0,0,0.1); text-decoration: none; color: #333; transition: 0.2s; }
.card:hover { background: #e8f4ff; }
table { width: 100%; border-collapse: collapse; background: white; box-shadow: 0 1px 4px rgba(0,0,0,0.05); }
th, td { padding: 10px; border: 1px solid #ddd; text-align: left; }
th { background: #0078D7; color: white; }